Vat dyestuffs by acid condensation of 2-benzanthronyl-1-amino-anthraquinones



Patented May 7, 1929.

UNITED STATES PATENT OFFICE;

HUGO WOL FF, OF 'MANNHEIM, GERMANY, ASSIGNOR TO GRASSELIJ DYESTUFF COR- PORATION, OF NEW YORK, N. Y.,

VAT D Y ESTUFFS BY ACID CONDENSATION A CORPORATION or DELAWARE.

OF 2-IBENZANTHRONYL-l-AMINO-ANTHBA QUINONES. v

No Drawing. Application filed July 2, 1927, Serial No. 203,254, and in Germany July 1, 1926.

5 nones.

I have now found that these substances, which are of low tinctorial value, on treatment with acid condensing agents, furnish new compounds of a distinct dyestuff character which produce fast'dyeings on vegetable fibres from the vat.

The following examples will further illusare heated to 125 C. with 100 parts of concentrated sulfuric acid and 2 parts of dry boric acid until thereaction is complete, the initially violet color of the melt changing quickly to a reddish brown. When the reaction is finished, the melt is. poured into water, boiled up and filtered. lhe resulting dyestuft is red in the form of a paste, and reddish brown when dried. It dissolves to a reddish brown solution in concentrated sulfuric acid, and also dissolves but with difliculty, to a brownish yellow solution in hot organic solvents of high boiling point. With an alkaline hydrosulphite solution a redbrown hydrocompound is formed even in the cold, passing into solution, with a brown-red color, when gently warmed, but green at higher temperatures. Reddish-brown dyeings are obtained on vegetable fibres from both vats, the color changing to a brilliant trate how the said invention may be carried into practical effect but the invention is not limited to these examples. The parts are by Weight.

Example 1.

10 parts of 2-benzanthronyl-1-aminoantln-aquinone, (which may be obtained by heating Q-chlorbenzanthrone and l-aminoanthraquinone in the presence of copper salts and acid-fixing agent in an organic solvent) and which corresponds to the formula at that temperature for about half an hour.

After cooling, the melt is decomposed with cold water and boiled up. The solution is filtered while hot, and the dyestufli' recovered in the form of paste or in the dry state. It is identical with that described in Example 1.

Ewample 3. i I

10 parts of the condensation product obtainable by the condensation of 2.6-dichlorbenzanthrone, having a melting .point of 230 C.,

with 2 molecules of l-aminoanthraquinone in the manner described in Example 1 and corresponding to the formula 5 are heated to from 125 to 130 C. with 150 parts of concentrated sulfuric acid for about an hour. The melt is treated in the manner described in example 1. The resulting dyestufl' is a brown powder which dis- 1 solves to an olive-brown solution in concentrated sulfuric acid, to olive-greenin oleum of 23 per cent stren th, and to green in sulfuric acid of 50 Be. strength. With an alkaline hydrosulphite solution it furnishes a 2 are heated as described in Example 1, with 100 parts df concentrated sulfuric acid until condensation is complete. The usual treatment furnishes a redish-brown paste, or when dried a dark brown powder, which dissolves to a brown val; from which brown dyeings are obtained on vegetable fibres.

Example 4.

red-brown solution in concentrated sulfuric acid, and to olive-green in 23 per cent oleum. Even in the cold, the dyestuif gives a redbrown vat with an alkaline hydrosulphite solution, the color changing to olive green when the solution is heated to about 70 C. Reddish-brown dyeings are obtained on vegetable fibres from both vats.

Ewample 5.

A mixture of 32 parts of anhydrous aluminium chlorid and 8 parts of common salt is heated at from 125 to 130 C. for about an hour with 5 parts of the condensation product obtainable from 1 molecule of 2-chlorbenzanthrone and 1 molecule of Lfi-diaminoam thraquinone in the manner described in E1:- ample l and corresponding to the formula.

& i

e l I The melt is treated as described in Example 2, and furnishes the dyestufi in the form. of a dark violet-brown paste, or dark brown powder, which dissolves to a reddish-brown solution in concentrated sulfuric acid or 23 per cent oleum, and to a violet-tinged red in sulfuric acid of B. strength. With acetic anhydride, to which a few'drops of concentrated sulfuric acid have been added, the dyestuff gives, on warming, an intensively can mine-red solution. Violet-brown dyeings are obtained on vegetable fibres from a red brown vat Example 6".

10 parts of the condensation product obtainable by condensing 1 molecule of 2.6-dichlorbenzanthrone and 1 molecule of Lamino- 4-methoxyanthraquinone in the manner described in Example 1 and probably corresponding to the formula OCHs are heated with 100parts of concentrated sulfuric acid, and worked up, in the manner specified in Example 3. The resulting dyestuff is in the form of a brown paste which ives, with an alkaline hydrosulphite solution, an olive-brown vat from which the fibre is dyed brown shades. The dyestufi dissolves to a reddish-brown solution in concentratgd sulfuric acid, and to a brown solution in 

